Jump to content
SAU Community

Recommended Posts

Hi Guys, my tuner disconnected the o2 sensor whilst tuning and forgot to connect it back after he was done with it.

I have since connected it back up and now the car idles funny when warm & backfires alot.

Would this have caused any issues because he tuned it when the o2 sensor was disconnected or would it be a totally unrelated problem ?

He also tuned it without a bov (blocked it off) but i got a GTR bov on there atm but i dont have the correct plumb back pipe so he blocked it, after i plumb it all up and get it running, would this affect the tune/cars drivebility & idle in anyway?

any help much appreciatyed.

Cheers

What ECU are you using?

you should be always tuning with the O2 switched off!

if its a powerFC, go into the settings menu, and disable it see how you go, if not enable it if it's disabled see how you go

i believe that the O2 sensor only trims the mixtures at cruise.

when tuning you turn the sensor off or you could unplug it. this allows the computer to not trim the mixtures and you get a true readout of what air fuel ratio you have.

but when youre under load the O2 sensor does nothing.

i am not running any at the moment in my GTR, still waiting on Nissan to get some in. the car runs fine, chews through a little more fuel than it should when cruising but other than that no difference.

its normal to turn off 02 feedback during tuning

but it should be re-enabled, the powerfc faq in my sig covers how to enable and check it

the blocked bov would make it stall and run like ass, fix that

im running a emanage ultimate.

oh ok fair enough, well its strange how the car idles funny when warm after connecting the 02 back up lol

ill get the bov sorted this weekend and see how it goes.

thanks guys :D

you cant turn feedback off with the ultimate so he may have tuned "around" it, leave it disconnected and run a tank through the car if your economy is fine leave it disconnected. I have on occasions had to do the same thing when a crook 02 sensor keeps 'pulling' the mixtures out of whack.

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now


  • Similar Content

  • Latest Posts

    • Oof, I will forevermore have those shredded gears in mind whenever someone talks about showing mechanical sympathy towards their car. Thanks for the photos, fascinating stuff!
    • Curious to see how the SpeedTek stuff holds up
    • The holdups last year were drivetrain related. I had the car out right after getting the bearing issue resolved. Third launch and the car didn't move after releasing the clutch. It had sheared all the engagement teeth off the 1st gear.    Thankfully no other damage was done. I set an aftermarket gear beside an OEM gear and found that the engagement teeth on the OEM gear were much larger and better supported. Looking through my bin of spare transmission gears I found that there are two types of tooth on the OEM first gears - the larger tooth and the smaller tooth. It looks like most aftermarket gearset manufacturers base their design on the smaller tooth. OEM large tooth left - Speedtek, OS Giken, etc or OEM small tooth right Decided to give that larger engagement tooth a try. Pressed the ring off an OEM gear and sent it to a transmission manufacturer here in the States. They did their "faceplating" operation with my synchro ring on the Speedtek gear.   I reassembled it, took it back to the track and promptly destroyed the gear itself.  I'll rebuild this and use it as a spare - thankfully just first gear and the countershaft are damaged beyond repair. Definitely disheartening but my welded on engagement tooth ring held up!  Moved to Speedtek's dog engagement design as the gears appear to be much stronger. So far they have taken much more abuse at the track. Also scored a Stillway lockout from the Netherands for super cheap. It's for some other RB transmission so it took a bit of fabrication to fit but honestly a very easy job. I also had to heavily modify the gates as they were very different.   Then for some reason at the last test and tune a silicon coupler below the throttle blew off and took out the radiator and fan. Thankfully it was in the burnout box and not down track. This car is really beating me up - I still haven't made a pass in it. Ran it through the gears many times on the street but it keeps biting me at the track.  Currently in the process of replacing the radiator and remaking the throttle pipe to remove the coupler and use a cast 90 and a vband. I WILL get this thing down the track...
    • Covers most of the above points really. There's a few exceptions but most just see driving as an irritating but necessary task they must complete if they want to get anywhere on time. Also see it as a good time to show their awesome multi-tasking abilities on their mobile and/or doing their makeup.  
    • I don't believe I posted pictures of the second oil pump pickup I added so here they are. Data shows it gets oil pressure up to the relief pressure much earlier in the RPM. Is that important? Not likely... This was just another attempt to fix the bearing issues.   I also heavily opened up the inlet to the pump since it now had to flow oil from two pickups. I believe the diameter increased about 1/8".
×
×
  • Create New...